Selection on variance in flowering time within and among individuals

Area of Science:

• Ecology
• Evolutionary Biology
• Plant Sciences

Background:

• Population flowering phenologies are influenced by flowering times within and among individual plants.
• Understanding the evolutionary dynamics requires examining phenotypic variances and heritabilities of flowering time traits.

Purpose of the Study:

• To model the impact of pollinator visitation rate and behavior on the short-term evolution of population flowering phenologies.
• To investigate how selection pressures, such as self-incompatibility and pollinator limitation, affect flowering time variances.

Main Methods:

• Phenotypic variance and heritability analysis of within-individual mean and variance of flowering time.
• Modeling ecological scenarios to assess selection impacts on flowering time distributions.
• Investigating the role of temporal autocorrelation in pollinator visitation rates.

Main Results:

• Selection does not correlate individual mean and variance of flowering time in the studied scenarios.
• Self-incompatibility and pollinator attraction lead to stabilizing selection, reducing within-individual variance.
• Pollinator limitation results in disruptive selection, increasing among-individual variance.
• Environmental stochasticity in pollinator rates selects for increased within-individual variance.

Conclusions:

• Pollinator interactions are key drivers in the evolution of flowering phenologies.
• The interplay of different selection types shapes both within- and among-individual variation in flowering time.
• Future research should empirically test these predictions by measuring genetic and selective parameters.